Aspirin
To be updated
Peak plasma levels in therapy are reached 1 to 3 hours after ingestion, but in overdose it may take up to 24 hours to reach a peak due to formation of insoluble concretions in the stomach. It is therefore recommended that levels are checked at 4 hours post-ingestion and then every 3 hours until a peak is achieved. Repeat samples are not justified however if the initial level is very low (ie. <20mg/L). Treatment depends on the peak plasma level and the presence of symptoms. Alkali therapy is sometimes indicated at levels as low as 350mg/L.Salicylate overdose results in dehydration, acid-base disturbance and electrolyte disorders, so frequent requests for U&E and blood gases may be made during treatment of the overdose.
1 Unless only a small amount is known to have been ingested (<15 g), institute lavage/emesis if within 12 hours of consumption.
2 If a large amount is known to have been taken or there are symptoms/signs of toxicity (e.g. tinnitus, hyperventilation) refer for treatment.
3 In other circumstances, glucose and electrolytes and plasma salicylate should be measured at 4 hours and treatment given if salicylate elevated (>500 mg/l).
